1. Field
The described technology relates generally to a light emitting device. More particularly, it relates to a light emitting device that emits light in response to electrons emitted due to an electric field, and a driving method thereof.
2. Description of the Related Art
A liquid crystal display (LCD), which is a kind of flat panel display, is a display device that forms images by changing a light transmission amount on a pixel basis using dielectric anisotropy of liquid crystal having a changing twist angle according to an applied voltage. Compared with a cathode ray tube, which is a conventional image display device, the LCD has a merit of decreased weight, thickness, and power consumption. The LCD includes a liquid crystal panel assembly and a light emitting device that is positioned at the rear side of the liquid crystal panel assembly to provide light to the liquid crystal panel assembly.
When the liquid crystal panel assembly is formed as an active liquid crystal panel assembly, the liquid crystal panel assembly includes a pair of transparent substrates, a liquid crystal layer positioned between the transparent substrates, a polarizing plate disposed at an outer surface of the transparent substrates, a common electrode located at an inside surface of one transparent substrate, pixel electrodes and switches that are provided at an inside surface of the other transparent substrate, and a color filter that provides red, green, and blue colors to three sub-pixels constituting a pixel. The liquid crystal panel assembly receives light that is emitted from a light emitting device, and forms images by transmitting or blocking the light with action of the liquid crystal layer.
Since a reaction time of liquid crystal is longer than one frame period, a motion blur phenomenon may occur in the LCD when an image having fast motion for each frame is realized so that a dim after-image is displayed on a screen. In order to solve the motion blur phenomenon, an impulsive method is used so that light sources of the light emitting device are turned on when an image is displayed for one frame and the light sources are turned off the rest of the time. In this way, an after-image of a previous frame is eliminated so that the motion blur phenomenon can be reduced. However, the impulsive method has a problem of causing a flicker phenomenon so that when a still image is displayed on the screen, the image flickers.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.